Structure of exhaust pipe

ABSTRACT

A structure of an exhaust pipe may include a first pipe discharging exhaust gas produced in engine cylinders disposed in a first side row, a second pipe discharging exhaust gas produced in engine cylinders disposed in a second side row, a merging pipe having a first end communicatively connected to the first pipe, and a second end communicatively connected to the second pipe, and a valve plate embedded in the merging pipe, and selectively closed or opened.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority to Korean Patent Application No. 10-2016-0045719, filed Apr. 14, 2016, the entire contents of which is incorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a structure of an exhaust pipe for a vehicle which discharges exhaust gas, which is generated in an engine, rearward from a vehicle body, and more particularly, to a structure of an exhaust pipe, which is capable of maintaining noise reducing properties or generating rough exhaust sound, which emphasizes dynamism, in accordance with a driving situation or a driver's preference.

Description of Related Art

Engines may be classified into an inline 4-cylinder engine, an inline 6-cylinder engine, a V6 cylinder engine, and a V8 cylinder engine in accordance with the number of cylinders and an arrangement state of the cylinders, and may also be classified into a longitudinal engine and a transverse engine in accordance with whether the engine is disposed in a width direction or a longitudinal direction of a vehicle body.

Among the engines, a longitudinal V6 cylinder engine may be configured such that exhaust pipes connected to cylinders in a left row and exhaust pipes connected to cylinders in a right row may be merged together at a middle portion, and a tone of exhaust sound varies in accordance with positions and shapes of the exhaust pipes being merged together.

That is, a basic frequency of the 6-cylinder engine having six cylinders is configured by orders of degrees basically including a 3rd order and a multiple of 3. However, it is known that as a result of actual analysis, a half-order such as a 1.5th order and a 4.5th order is also present.

The distribution of the half-order is known as a main factor that determines a tone of exhaust sound of a vehicle, and it is known that the distribution of the half-order occurs due to a change in exhaust timing of the engine or imbalance of a length of an intake runner or an exhaust runner.

For reference, an analysis of frequencies of sound generated by the engine is carried out by analyzing a degree of order defined by one event per revolution of a crankshaft, a basic frequency of discharge sound of exhaust gas varies in accordance with a rotational speed and the order of the engine (if a typical frequency analysis method is used for a rotating body, a vibration frequency of which varies in accordance with a rotational speed of the engine, there is a problem in that the vibration frequency often varies in accordance with a rotational speed of the engine). Therefore, there is a limitation in finding a cause of vibration and solving the problems only by using the frequency analysis method, and as a result, an order analysis method, which is a concept for non-dimensionalizing vibration components associated with a rotational speed by using an input rotational speed which is a cause of a change in frequency, is widely used in the art for a vibration system a vibration frequency of which varies as a rotational speed is often changed. That is, the input rotational speed is measured at all times, and the input rotational speed is indicated by a primary order, and vibration associated with the input rotational speed is indicated by an order component [a multiple, a degree, etc.], and as a result, a component associated with the input rotational speed may always be indicated by a constant order component regardless of the input rotational speed.

Meanwhile, quality of exhaust sound having a number of half-order components (H1.5, H4.5 . . . ) shows a very rough tone. Therefore, a vehicle, which requires noise reducing properties, is set such that the half-order component is reduced, but a vehicle with specialized high performance, which aims to maximize driving performance, rather improves marketability by emitting rough exhaust sound.

In a structure in the related art which is mounted in a large-scaled passenger vehicle and in which noise reducing properties are considered as being important, a left exhaust pipe 1 and a right exhaust pipe 2 are connected to each other through sub-mufflers 3 a and 3 b, and define a merging portion 4 which allows the both exhaust pipes to communicate with each other (so that exhaust gas flowing in both of the exhaust pipes may be merged together), as illustrated in FIG. 1A, thereby improving noise reducing properties by weakening the overall section of the half-order.

However, the aforementioned structure cannot appeal to consumers who prefer rough exhaust sound as described above, and there is a need for development of a structure of an exhaust pipe which may emphasize the half-order, that is, produce rough exhaust sound in accordance with a driving condition.

The aforementioned structure in the related art is very vulnerable to vibration because heavyweight mufflers 6 a and 6 b having a long left and right mounting length are mounted to the structure, and as a result, a reinforcing bracket 5 for improving a vibration mode is separately and additionally mounted. That is, as illustrated in FIGS. 1B and 1C, unnecessary behavior of the mufflers 6 a and 6 b may occur in an up and down direction and a left and right direction, and vibration of the mufflers 6 a and 6 b is excessively increased in the up and down direction and the left and right direction when excitation vibration of the engine occurs and the mufflers 6 a and 6 b resonate, and as a result, there is concern that vibration of the vehicle body will increase and booming sound will occur. To solve a problem with the occurrence of vibration, a support body is required to be additionally mounted across the left exhaust pipe 1 and the right exhaust pipe 2, and in the related art, the reinforcing bracket 5 is additionally mounted as the support body.

BRIEF SUMMARY

Various aspects of the present invention are directed to providing a structure of an exhaust pipe, which is capable of maintaining noise reducing properties or generating exhaust sound, which emphasizes dynamism, in accordance with a driving situation or a driver's preference so as to meet the requirement of development, and making it unnecessary to additionally mount a reinforcing bracket separately from a merging portion.

According to various aspects of the present invention, a structure of an exhaust pipe may include a first pipe discharging exhaust gas produced in engine cylinders disposed in a first side row, a second pipe discharging exhaust gas produced in engine cylinders disposed in a second side row, a merging pipe having a first end communicatively connected to the first pipe, and a second end communicatively connected to the second pipe, and a valve plate embedded in the merging pipe, and selectively closed or opened.

The valve plate may have a circular plate shape, and may be configured to be opened or closed based on a rotation angle at which a rotating shaft is rotated.

The structure may further include an actuator which rotates the valve plate when electric power is applied to the actuator.

The actuator may open or close the valve plate based on driving information of the vehicle and predetermined logic, and rotate the valve plate so as to open or close the valve plate.

The actuator may open the valve plate under a condition in which the engine operates at a range of 750 rpm to 3,000 rpm, and an engine load is 50% or below.

The first pipe and the second pipe may form sections in which the first pipe and the second pipe are parallel to each other at a front side of a muffler, and the merging pipe may be disposed in the section in which the first pipe and the second pipe are parallel to each other.

Pipe joints may be mounted at both ends of the merging pipe, respectively, to be fitted in the section in which the first pipe and the second pipe are parallel to each other.

The various embodiments of the present invention having the aforementioned configuration may generate silent exhaust sound or dynamic exhaust sound by adjusting communication between the first pipe and the second pipe in accordance with a driving situation or a driver's intention, thereby further improving marketability of a vehicle.

The merging pipe according to various embodiments of the present invention may be mounted at a position where a reinforcing bracket in the related art for improving a vibration mode is disposed (i.e., within a section in which the first pipe and the second pipe are parallel to each other between the sub-muffler and the muffler), and may be substituted for the reinforcing bracket.

The actuator, which controls the valve plate, is configured to operate by predetermined logic, and may implement various types of exhaust sound in accordance with properties of the vehicle or a mode manipulated by the driver.

It is understood that the term “vehicle” or “vehicular” or other similar terms as used herein is inclusive of motor vehicles in general such as passenger automobiles including sports utility vehicles (SUV), buses, trucks, various commercial vehicles, watercraft including a variety of boats and ships, aircraft, and the like, and includes hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles and other alternative fuel vehicles (e.g., fuel derived from resources other than petroleum). As referred to herein, a hybrid vehicle is a vehicle that has two or more sources of power, for example, both gasoline-powered and electric-powered vehicles.

The methods and apparatuses of the present invention have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description, which together serve to explain certain principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a view illustrating an exhaust pipe in the related art.

FIG. 1B and FIG. 1C are views illustrating a state in which behavior occurs at the periphery of a muffler in an up and down direction and a left and right direction in the exhaust pipe in the related art.

FIG. 2 is a view illustrating an appearance of an exhaust pipe according to various embodiments of the present invention, and an enlarged portion where a merging pipe is mounted.

FIG. 3 is a view illustrating an appearance of the merging pipe according to various embodiments of the present invention, in which an interior of the merging pipe is penetrated in order to show an embedded valve plate.

FIG. 4 is a view illustrating an appearance of a cross section when an interior of the valve plate is opened and closed.

It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that the present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims.

Various embodiments of the present invention relate to a structure of an exhaust pipe which is capable of maintaining noise reducing properties or generating rough exhaust sound, which emphasizes dynamism, in accordance with a driving situation or a driver's preference, and hereinafter, various embodiments of the present invention will be described in more detail with reference to the drawings.

As illustrated in FIG. 2, in an exhaust pipe according to various embodiments of the present invention, a first pipe 10, which discharges exhaust gas produced in engine cylinders disposed in one side row, and a second pipe 20, which discharges exhaust gas produced in engine cylinders disposed in the other side row, are disposed in parallel in a longitudinal direction, and connected through a merging pipe 30. That is, the merging pipe 30 has one end which is connected with the first pipe 10 so as to communicate with the first pipe 10, and the other end which is connected with the second pipe 20 so as to communicate with the second pipe 20, and a valve plate 32, which is opened and closed, is embedded in the merging pipe 30 as illustrated in FIG. 3.

In various embodiments of the present invention, the merging pipe 30 has a cylindrical shape, and the valve plate 32 is formed in a circular shape having a diameter capable of closing the merging pipe, and the valve plate 32 is configured to be opened or closed based on a rotation angle at which a rotating shaft is rotated.

When electric power is applied to the valve plate 32, the valve plate 32 is coupled to an actuator 50 being rotated by an embedded motor. The actuator 50 determines whether to open or close the valve plate 32 based on driving information of the vehicle and predetermined logic, and may be set to rotate the valve plate 32 so as to open or close the valve plate 32.

The actuator 50 may be set to open the valve plate 32 so as to reduce exhaust sound (to reduce a half-order component) under a condition in which the engine operates at a low rotational speed within a range of 750 rpm to 3000 rpm, and an engine load is below 50%, but the actuator 50 may be set to close the valve plate 32 so as to generate rough exhaust sound (to prevent a reduction in the half-order component) under a condition in which the engine operates at a high rotational speed of 3,000 rpm or higher.

Alternatively, independently of the aforementioned setting, the actuator 50 may be adjusted to generate rough exhaust sound or silent exhaust sound at all times based on a driver's preference or only in a particular situation.

Meanwhile, as illustrated in FIGS. 2 and 4, in various embodiments of the present invention, sub-mufflers 11 and 21 are disposed on the first pipe 10 and the second pipe 20, respectively, at front sides of mufflers 40, and sections 10 a and 20 a, in which the first pipe 10 and the second pipe 20 are parallel to each other, are formed between the sub-mufflers 11 and 21 and the mufflers 40, and the merging pipe 30 is configured to be disposed in the sections 10 a and 20 a in which the first pipe 10 and the second pipe 20 are parallel to each other.

Pipe joints 31 are mounted at both ends of the merging pipe 30 so as to be fitted in the sections 10 a and 20 a in which the first pipe 10 and the second pipe 20 are parallel to each other.

According to various embodiments of the present invention having the aforementioned configuration, when the engine operates at a low speed, the valve plate 32 is opened such that exhaust gas at both sides of the merging pipe 30 is merged together, and as a result, the half-order is weakened and exhaust sound becomes silent like the structure in the related art. Further, when the engine operates at a high speed, the valve plate 32 closes the merging pipe 30 such that exhaust gas at both sides is blocked, and as a result, the half-order is prevented from being weakened and rough and dynamic exhaust sound is generated unlike the structure in the related art.

The merging pipe 30 according to various embodiments of the present invention supports and connects the first pipe 10 and the second pipe 20, and as a result, torsional rigidity is further increased by the merging pipe 30 instead of the reinforcing bracket in the related art.

Meanwhile, the actuator 50, which controls the valve plate 32, is configured to operate by predetermined logic, and may implement various types of exhaust sound in accordance with properties of the vehicle or a mode manipulated by the driver.

The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents. 

What is claimed is:
 1. A structure of an exhaust pipe, the structure comprising: a first pipe discharging exhaust gas produced in engine cylinders disposed in a first side row; a second pipe discharging exhaust gas produced in engine cylinders disposed in a second side row; a merging pipe having a first end communicatively connected to the first pipe, and a second end communicatively connected to the second pipe; and a valve plate embedded in the merging pipe, and selectively closed or opened.
 2. The structure of claim 1, wherein the valve plate has a circular plate shape, and is configured to be opened or closed based on a rotation angle at which a rotating shaft is rotated.
 3. The structure of claim 2, further comprising an actuator which rotates the valve plate when electric power is applied to the actuator.
 4. The structure of claim 3, wherein the actuator opens or closes the valve plate based on driving information of the vehicle and predetermined logic, and rotates the valve plate to open or close the valve plate.
 5. The structure of claim 4, wherein the actuator opens the valve plate under a condition in which the engine operates at a range of 750 rpm to 3,000 rpm, and an engine load is 50% or below.
 6. The structure of claim 1, wherein the first pipe and the second pipe form sections in which the first pipe and the second pipe are parallel to each other at a front side of a muffler, and the merging pipe is disposed in the section in which the first pipe and the second pipe are parallel to each other.
 7. The structure of claim 6, wherein pipe joints are mounted at both ends of the merging pipe, respectively, to be fitted in the section in which the first pipe and the second pipe are parallel to each other. 